Mortgage lenders ask for a letter of explanation to better understand your finances when determining whether to approve you for a loan. Say you have a mortgage and want to know exactly how much you'd need to pay to satisfy the loan.A mortgage payoff letter will tell you that magic number. Goodwill letter template. A letter of explanation is a brief document you can use to explain something, like a previous bankruptcy, in your financial or employment history. Goodwill letter template. The Mortgagee must document this analysis in the mortgage file. The notes are owned by, or titled in the name of, a third party (for example, mortgages that are subject to a sale and repurchase arrangement); or.